Sigma Virginis
Star in the constellation Virgo
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Sigma Virginis (σ Vir, σ Virginis) is a star in the zodiac constellation of Virgo. It can be faintly seen with the naked eye with a baseline apparent visual magnitude of 4.86.[2] Based upon parallax measurements, the distance to this star is roughly 680 light-years.
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 13h 17m 36.28327s[1] |
| Declination | +05° 28′ 11.5221″[1] |
| Apparent magnitude (V) | 4.86[2] |
| Characteristics | |
| Spectral type | M1 III[3] |
| U−B color index | +1.86[2] |
| B−V color index | +1.62[2] |
| Variable type | suspected[4] |
| Astrometry | |
| Radial velocity (Rv) | −28.26±0.30[5] km/s |
| Proper motion (μ) | RA: −6.06[1] mas/yr Dec.: +9.14[1] mas/yr |
| Parallax (π) | 4.83±0.19 mas[1] |
| Distance | 680 ± 30 ly (207 ± 8 pc) |
| Absolute magnitude (MV) | −1.80[6] |
| Details | |
| Radius | 98[7] R☉ |
| Luminosity | 1,610[7] L☉ |
| Surface gravity (log g) | 0.42[7] cgs |
| Temperature | 3,690[7] K |
| Other designations | |
| σ Vir, 60 Virginis, BD+06°2722, FK5 1344, HD 115521, HIP 64852, HR 5015, SAO 119855[8] | |
| Database references | |
| SIMBAD | data |
This is an evolved red giant star with a stellar classification of M1 III.[3] It is a suspected variable star with a brightness that ranges from magnitude +4.77 to +4.86.[4] This variation has pulsation periods of 23.4, 24.3, 27.9 and 34.1 days.[3] The effective temperature of the stellar atmosphere is around 3,800 K, and it shines with 1,734 times the luminosity of the Sun.[7]